There is known a plurality of various solutions for coaxial connection two pipe ends. In particular there exist many solutions for connection of riser segments into riser strings suited to extend through the sea down to a subsea well. Such strings of riser segments need to withstand large and varying forces, and the connections need to preserve a sealed connection between each riser segment.
In some types of connections a plurality of locking segments is arranged about the two facing pipe ends. The locking segments have inwardly facing locking profiles which engage with outwardly facing locking profiles of the respective pipe ends. In order to better withstand the large and varying forces, the locking segments are provided with a preload when in the locking position.
European patent application publication EP367419 describes such a connection. A plurality of locking segments are forced into locking engagement with the two facing pipe ends by two externally arranged locking rings. By forcing the two locking rings axially towards each other, the locking segments are forced radially inwards into the locking position. The two locking rings can be moved in the axial direction by actuation of nuts threaded onto bolts that extend through the two locking rings.
Patent publication U.S. Pat. No. 4,557,508 describes a similar solution where one actuation ring with an inclined inner face forces the locking segments inwards into locking position when being moved in an axial direction.
Patent publication U.S. Pat. No. 5,634,671 describes a riser connector having a split lock ring with inner profiles which are adapted to engage with facing outer locking profiles on both ends of two adjacent riser pipe ends. The profiles exhibit inclined sliding faces which provide a preload in the lock ring when the latter is forced radially into the locking profiles of the pipe ends. The split lock ring extends axially between the two pipe ends and connects them together when in the locking position. When in the locking position, a set of actuating cam rings remains in contact with the lock ring in order to retain the ring in this position.
It is an object of the present invention to provide a connection assembly suitable for connection of facing and coaxially arranged pipe ends, wherein the connection assembly exhibits a lean radial extension and facilitates a quick connection process. Other advantageous objects being complied with will appear from the general description and the detailed embodiment description below.